OD tranny

["Eric Myracle" <eric_myracle@hotmail.com>]

Hello list.  As I was driving around with the top down today I thought
"it sure would be nice to have overdrive on this thing".  How much
work and cost is it to retrofit a non-OD TR6 (1970 model) to have OD?
Can the OD be appended to the tranny, or is it best to find a
tranny+OD assembly and the shorter driveshaft all from a different
car?  I guess I'd need a relay and an interior switch too (were they
on the dash, steering column, or shifter?)

Thanks,
Eric